The long-term goal is to provide new methods for statistical analysis of linkage data in gene mapping, thereby increasing reliability and precision of resulting estimates. Also, on a long-term basis, to provide reliable and generally available support for software in linkage analysis. The specific aims focus on three areas of the human genome project. They all address methodological problems in statistical genetics by proposing either development of new methods or improvement of existing methods. Some of the current methods need to be adapted to the present status of the genome project, that is, to take advantage of the availability of a dense map of markers. The first two specific aims are directed towards methodology in genetic mapping and the last specific aim focusses on dissemination of technology and on technical and methodological support of researchers in gene mapping. The following three specific aims are set forth, with each aim consisting of a small number of components: 1. Methods for improving the accuracy of the genetic map (Trend of sex ratio in recombination fractions; Investigation of crossover distributions; Analysis of chromosome maps). 2. Methods for mapping disease genes (Recessive diseases: Estimating relationship among parents; Recessive diseases: Allele frequency estimation via IBD; Linkage analysis and linkage disequilibrium). 3. Dissemination of methodology (To implement newly developed methods in computer programs and add them to the current collection of computer programs for genetic-mapping; To maintain and update these programs, and to make them available to researchers; To circulate a Linkage Newsletter; To support users in the application of linkage programs through collaborative arrangements).